System for carrying out mechanical workings

ABSTRACT

A machine for carrying out mechanical workings preferably by shaving removal comprises frame means ( 4 ) arranged for receiving a semi-worked piece (P) to be worked, the semi-worked piece (P) having a cross section exhibiting dimensions remarkably smaller than the length of the piece (P) measured along its own longitudinal axis, and said semi-worked piece (P) being arranged with said longitudinal axis along a working axis (Z 1 ; Z 2 ; Z 3 ) in a working station, clamp means ( 46 ) arranged at a plurality of cross sections of said semi-worked piece (P) for locking said semi-worked piece (P) in said working station, tool means ( 29 ) arranged for carrying out workings on faces of said semi-worked piece (P), supporting means ( 16, 5 ) to which said semi-worked piece is fixed by said clamp means ( 46 ), said supporting means ( 16, 5 ) being suitable to be rotated about a service axis (Z).

[0001] The invention relates to single-spindle machine, method and apparatus for carrying out mechanical workings, preferably by shaving removal on elongated mechanical parts, such as general semi-worked pieces.

[0002] Prior art comprises machine tools for working profiled elements, for example made of aluminium or PVC, wherein the profiled elements, consisting of bars often having even remarkable length, are arranged in a fixed working position with respect to a base-frame and are kept in that position through a plurality of fastening clamps. A moving trolley, carrying motorized groups of tools, is positioned at pre-established, longitudinally consecutive, cross sections of the profiled element in order to perform on each section the required mechanical workings.

[0003] A first limitation of these known machines consists in that, the downwards face of the profiled element to be worked, i.e. the one adjacent to the machine bed, is poorly accessible and then difficult to be worked, since the base-frame overall dimensions hamper tool approach to the profiled element.

[0004] Workings on the face adjacent to the machine bed are performed through operating heads with mechanical transmission of motion, which are placed faraway from the supports and are therefore not very accurate. However, these operating heads can only perform relatively simple operations.

[0005] Consequently, if the profiled element has to be subjected to complex workings also on the face adjacent to the machine bed, it is necessary to position it again on the machine after rotating it of a suitable angle about its own longitudinal axis, so that the face, which was previously difficult to be machined, is now easily accessible by a suitable tool, or group of tools.

[0006] A further limitation of such machines can be found in the heavy impact of loading and unloading idle times on the working cycle: actually, when the planned working sequence on a single profiled element is finished, it is necessary to pick it up in order to clear the working position on the machine and to carry in that position another element which has still to be worked; the already worked element clearing phase and the still to be worked element positioning phase, during which it is not possible to carry out any machining on the profiled element, imply a remarkable waste of time, particularly if—as it often happens—the elements to be worked are considerably voluminous.

[0007] In addition, clamps are known for locking the profiled elements to be worked on the bed of such machines, wherein locking of each clamp is provided by feeding compressed air to pneumatic actuating members that keep each clamp in a pre-established position while locking it on the guides. These clamps have the disadvantage of requiring a complex air supplying circuit and furthermore, if the air pressure accidentally decreases, the clamps result substantially free to move along the guides, which implies risks of failures and accidents for personnel in charge.

[0008] Furthermore, the known machines require that the profiled element is at first placed in a working station, subsequently worked in that station and then unloaded. This implies the disadvantage that the profiled element machining has to be stopped during the positioning and unloading operations of the profiled element from the working station: that produces excessively long cycle times.

[0009] Therefore, the problem arises of improving the known systems for carrying out mechanical workings on profiled elements. More in particular, it is desirable that it is possible to carry out the required workings on every face of the profiled element.

[0010] Furthermore, it is desired to find a more efficient working system for profiled elements, i.e. wherein the impact of loading and unloading times is remarkably reduced.

[0011] In addition, it is desired to find a new clamps actuation structure which is more reliable and simple.

[0012] In a first aspect of the invention, a machine is provided for carrying out mechanical workings preferably by shaving removal, comprising frame means arranged for receiving a semi-worked piece to be worked, the semi-worked piece having a cross section exhibiting dimensions remarkably smaller than the length of the piece measured along its own longitudinal axis, said semi-worked piece being arranged with said longitudinal axis along a working axis in a working station, clamp means arranged at a plurality of cross sections of said semi-worked piece for locking said semi-worked piece in said working station, tool means arranged for carrying out workings on faces of said semi-worked piece, characterized in that, supporting means is provided to which said semi-worked piece is fixed by said clamp means, said supporting means being suitable to be rotated about a service axis.

[0013] In a version, the service axis is coincident with said working axis.

[0014] In this case, as supporting means is provided, it is possible to machine all the faces of the semi-worked piece, since, after carrying out mechanical workings on the semi-worked piece faces directly accessible by tool means, it is possible to rotate the, supporting means in order to work the remaining face or faces, without removing the semi-worked piece from the working station.

[0015] In a further version, the service axis can be positioned parallel to said working axis.

[0016] This allows the supporting means to be equipped with more than one semi-worked piece; it is therefore possible, for example, after completing workings on a semi-worked piece, to rotate the supporting means in order to bring the already worked semi-worked piece into an unloading station, and simultaneously bring a still to be worked semi-worked piece into the working station.

[0017] Advantageously, the supporting means comprises first supporting means arranged for rotating the semi-worked piece about said working axis and second supporting means arranged for rotating the first supporting means, together with the semi-worked piece associated thereto, about a service axis parallel to said working axis.

[0018] This allows all the faces of the semi-worked piece to be machined without removing it from the working station, the already worked semi-worked piece to be quickly unloaded from the working station and a still to be worked semi-worked piece to be loaded in said station.

[0019] Advantageously, the working axis and the service axis are arranged in vertical position.

[0020] It is thus possible to obtain a machine for working semi-worked pieces having very reduced plant overall dimensions. Furthermore, such a machine can be easily soundproofed.

[0021] If a vertical arrangement for such a machine is provided, the user can collect downwards the shavings produced when machining the semi-worked piece and can remove them in a very simple way.

[0022] Finally, in a vertically developed machine, the semi-worked piece to be worked can be positioned in the optimal manner, as, since it is a slender piece, it would show a tendency to bend under its own weight if it were arranged horizontally.

[0023] In a second aspect of the invention, clamp means is provided slidably coupled on guide means and arranged for locking a semi-worked piece, at cross sections taken along its length, through pliers means driven by suitable actuating means, characterized in that, said clamp means is provided with mechanical locking means suitable to lock said clamp means onto said guide means.

[0024] Since mechanical locking means is used for locking the clamps a greater positioning reliability can be obtained, which prevents a complex and bulky pneumatic circuit for compressed air supplying to be arranged.

[0025] In a third aspect of the present invention, a method is provided for working semi-worked elements, comprising placing a semi-worked piece in a working station, characterized in that, substantially simultaneously to said placing it is further provided placing a semi-worked piece to be worked in a loading station and extracting a semi-worked piece already worked from an unloading station.

[0026] In this way, the semi-worked piece working cycle is made particularly efficient since auxiliary working steps are performed while semi-worked piece working is in progress, instead of being performed before or after working is carried out as in traditional systems.

[0027] The invention will be better understood and carried out with reference to the attached drawings, which show an exemplifying and not restrictive embodiment thereof, in which:

[0028]FIG. 1 is a perspective view of a machine for working semi-worked pieces;

[0029]FIG. 2 is an intermediate section of the machine of FIG. 1, along a horizontal plane;

[0030]FIG. 3 is a top view of the machine of FIG. 1;

[0031]FIG. 4 is a vertical section, taken along the plane IV-IV of FIG. 3;

[0032]FIG. 5 is a perspective view of cradle means wherein semi-worked pieces to be worked are arranged;

[0033]FIG. 6 is a perspective view of clamp means for fastening the semi-worked piece;

[0034]FIG. 7 is a sketched view of the clamp means, highlighting the positioning mechanism over the guides thereof;

[0035]FIG. 8 is a sketched view of the clamp means highlighting the positioning mechanism over the guides in an operational variation.

[0036] As shown in FIGS. 1, 2 and 3, a machine 2 comprises a frame 4 to which a carousel 5 is supported, which is indexed at angular steps of 120° about a vertical axis indicated by Z in FIG. 2. In the front portion of frame 4 are defined a loading station 6, wherein semi-worked, raw pieces P are introduced into the machine 2 (FIG. 7), an unloading station 8 wherein already worked semi-worked pieces are extracted from the machine 2 and a foot platform 10 accessible through small stairs 12 in order to allow an operator to approach the loading station 6 and the unloading station 8.

[0037] In the rear portion of the frame 4 a working station 14 is arranged, wherein the semi-worked piece undergoes the required workings.

[0038] Frame 4 completely surrounds the operating parts of the machine 2, so that the machine can be completely closed by sound absorption and soundproof panels preventing noise from escaping towards external environment and furthermore forming a protection barrier against accidental shavings escape, or entrance of people who could be injured.

[0039] Cradles 16 are supported to the carousel 5, so as to be rotatable about further vertical axes Z1, Z2, Z3, and spaced one from the other by a 120° angular step. Between each cradle 16 and the adjacent cradle 16 a separating panel 18 is arranged, fixed to the carousel 5. In this way, when a cradle 16, carrying a semi-worked piece to be worked, stands in the working station 14, the panels 18 adjacent to the cradle 16 make the working station 14 substantially inaccessible.

[0040] On the top of frame 4 a gear motor unit 20 is mounted, movable by a linear actuator 24 along guides fixed to cross-beams 22 of the frame 4, so as a driving gear wheel 20 a of the gear motor unit 20 alternatively engages a crown gear 26, fixed to the carousel 5, or a pinion 28 fixed to each cradle 16 at the further vertical axis Z1, Z2 or Z3. The further vertical axes Z1, Z2, Z3 define a circle C during their revolution motion around the axis Z.

[0041] In a working configuration, the gear motor unit 20 engages the crown gear 26 when the carousel 5 has to be rotated by a 120° angle in order to bring an already worked semi-worked piece P to the unloading station 8 and a still to be worked semi-worked piece to the working station 14.

[0042] In another working configuration, the gear motor unit 20 engages the pinion 28 of the cradle 16 standing in the working station 14 and turns to a spindle 29 a working face of the semi-worked piece to be worked.

[0043] The spindle 29 is supported by a cross-beam 30 which is in engagement with vertical guides 32 fixed to the frame 4 and which may be vertically positioned through toothed belts 34 wound around respective pulleys that can be rotatably driven by a shaft 36 coupled to a gear motor 38.

[0044] Each cradle 16 is axially delimited by a couple of end flanges 40 interconnected to each other through a couple of uprights 42 on which guide means 44 are obtained. The guide means 44 are suitable to slidably receive clamp means 46 arranged in sufficient number to assure a proper locking of the semi-worked piece P during its working and transferring.

[0045] As FIG. 4 shows in detail, the upper portion of carousel 5 is rotationally coupled to a pin 50 fixed to the frame 4 through a bearing 48 interposed between the pin 50 and a hub 52, to which the crown gear 26 is connected. The hub 52 is fixed to an upper plate 54 delimiting the upper end of the carousel 5.

[0046] At the further vertical axis Z1, Z2 or Z3, each flange 40 is provided with an appendix 56 passing through the upper plate 54 and rotationally coupled to it through rolling means 58 interposed between the appendix 56 and sleeve means 59 fixed to the upper plate 54.

[0047] As highlighted in FIGS. 5, 6 and 7, each clamp means 46 is equipped with a cross-beam body 60 provided with ends engaging the guide means 44 and terminating with a hook-like shape 61 in order to surround the uprights 42. First actuating means 62 and second actuating means 64 are fixed to the cross-beam body 60. The first actuating means 62 has the function to position first locking means 66, removing them from or moving them close to the cross-beam body 60 along a transversal direction F1 in order respectively to release or lock a profiled portion of the semi-worked piece P, arranged near said first locking means. The second actuating means 64 has the function to remove second locking means 68 from and move them close to the first locking means 66 along a longitudinal direction F2, in order respectively to lock a profiled portion of the semi-worked piece P to be worked against the first locking means 66, and release it therefrom, said profiled portion being arranged near said second locking means.

[0048] In the cross-beam body 60 a mechanism is inserted, arranged for releasing or fixing the clamp means 46 on the uprights 42. The mechanism comprises an actuating rod 70 axially slidable under the action of an external thrust acting at fine end thereof (exerted by suitable linear actuating means not shown) and actuating at the opposite end a rocker arm 72 centrally arranged in the cross-beam body 60 for driving a couple of actuating levers 74 acting on friction pads 76 through swinging levers 78 against the action of elastic means 80.

[0049] The friction pads 76 operate on brake lining surfaces of the uprights 42.

[0050] In the version shown in FIG. 8, the actuating rod 70 directly operates on the ends of a couple of driven rods 84 bringing at the opposite ends the friction pads 76. The actuating rod 70 is provided with inclined planes 86 arranged in such a way that when the actuating rod 70 is pushed towards the inner part of the cross-beam 60, the driven rods 84 are free to enter the body of the cross-beam 70 under the action of elastic return means 88, releasing therefore the guide means 44 from the pads 76, in order to allow longitudinal positioning of the clamp along the guide means under the action of suitable linear actuating means not shown. When the force acting on the actuating rod 70 is stopped, the actuating rod 70 comes back in its initial position pressing again the driven rods 84 with the pads 76 against the guides 44. 

1. Machine for carrying out mechanical workings preferably by shaving removal, comprising frame means (4) arranged for receiving a semi-worked piece (P) to be worked, the semi-worked piece (P) having a cross section exhibiting dimensions remarkably smaller than the length of the piece (P) measured along its own longitudinal axis, said semi-worked piece (P) being arranged with said longitudinal axis along a working axis (Z1; Z2; Z3) in a working station, clamp means (46) arranged at a plurality of cross sections of said semi-worked piece (P) for locking said semi-worked piece (P) in said working station, tool means (29) arranged for carrying out workings on faces of said semi-worked piece (P), characterized in that, supporting means (16, 5) is provided to which said semi-worked piece is fixed by said clamp means (46), said supporting means (16, 5) being suitable to be rotated about a service axis (Z).
 2. Machine according to claim 1, wherein said service axis is coincident with said working axis.
 3. Machine according to claim 1, wherein said service axis (Z) is arranged parallel to said working axis (Z1; Z2; Z3).
 4. Machine according to any one of the preceding claims, wherein said working axis (Z1; Z2; Z3) and said service axis (Z) are arranged in a vertical position.
 5. Machine according to any one of the preceding claims, and further comprising a loading station (6) wherein said semi-worked piece (P), in a raw condition, is introduced into said machine (2).
 6. Machine according to any one of the preceding claims, and further comprising an unloading station. (8) wherein said semi-worked piece (P), already worked, is extracted from said machine (2).
 7. Machine according to any one of the preceding claims, wherein said supporting means comprises first supporting means (16) arranged for rotating said semi-worked piece about said working axis (Z1; Z2; Z3).
 8. Machine according to claim 7, as appended to any one of claims from 3 to 6, wherein said first supporting means (16) is arranged for rotating in second supporting means (5), said second supporting means (5) being arranged for rotating said first supporting means (16) with the semi-worked piece (P) associated thereto about said service axis (Z).
 9. Machine according to claim 8, wherein a plurality of said first supporting means (16) is mounted on said second supporting means (5), said second supporting means (5) being arranged for rotating said first supporting means (16) about said service axis (Z) so as to bring successively each one of said first supporting means (16) into said working station, into said unloading station and into said loading station.
 10. Machine according to any one of claims from 3 to 9, wherein a gear motor unit (20) is mounted on the top of said frame means (4), movable on said frame means (4) so as to engage alternatively said first supporting means (16) at said working axis (Z1; Z2; Z3), or said second supporting means (5) at said service axis (Z).
 11. Machine according to claim 10, wherein said gear motor unit (20) is movable on said frame means (4) through actuating means (24).
 12. Machine according to claim 10, or 11, wherein said gear motor unit (20) is provided with gear motor means (20 a) arranged for engaging gear driven means (26; 28) of said first supporting means (16), or respectively of said second supporting means (5).
 13. Machine according to any one of the preceding claims, wherein said second supporting means (5) shows an upper portion rotationally coupled to a pin (50) fixed to said frame means (4) through a bearing (48) interposed between said pin (50) and a hub (52) of said second supporting means (5).
 14. Machine according to claims 12 and 13, wherein said gear driven means comprises a crown gear (26) delimiting said upper portion.
 15. Machine according to any one of claims from 12 to 14, wherein said gear driven means comprises a pinion (28) of said first supporting means (16).
 16. Machine according to any one of claims from 7 to 15, wherein each of said first supporting means (16) is axially delimited by a couple of end flanges (40), interconnected to each other by a couple of uprights (42).
 17. Machine according to claim 16, wherein guide means (44) is obtained on said couple of uprights (42), said guide means (44) being suitable to slidably receive said clamp means (46).
 18. Machine according to claim 16, or 17, wherein each flange (40), belonging to said couple of flanges, is provided, at said working axis (Z1; Z2; Z3) with an appendix (56) passing through an upper plate (54) of said second supporting means (5).
 19. Machine according to claim 18, wherein said appendix (56) is rotatably coupled to said upper plate (54) through rolling means (58) interposed between said appendix (56) and sleeve means (59) fixed to said upper plate (54).
 20. Machine according to any one of claims from 3 to 19, wherein wall means (18) is interposed between each of said first supporting means (16) and the adjacent first supporting means (16), said wall means (18). being suitable to define compartments arranged for singularly containing said first supporting means (16).
 21. Machine according to any one of the preceding claims, wherein said tool means (29) is supported by a cross-beam (30) which is in engagement with vertical guides (32) fixed to said frame means (4).
 22. Machine according to claim 21, wherein said cross-beam (30) is vertically positionable through toothed belts (34) wound around respective pulleys suitable to be rotated by a shaft (36) coupled to a further gear motor (38).
 23. Clamp means slidably coupled on guide means (44) and arranged for locking a semi-worked piece (P), at cross sections taken along its length, through pliers means (66, 68) driven by suitable actuating means (60, 62), characterized in that, said clamp means (46) is provided with mechanical locking means suitable to lock said clamp means (46) onto said guide means (44).
 24. Clamp means according to claim 23 and further comprising a cross-beam body (60) having ends engaging said guide means (44) and terminating with a hook-like shape (61).
 25. Clamp means according to claim 23, or 24, wherein said actuating means comprises first actuating means (62) and second actuating means (64).
 26. Clamp means according to any one of claims from 23 to 25, wherein said pliers means comprises first pliers means (66) and second pliers means (68).
 27. Clamp means according to claim 24, wherein said mechanism comprises an actuating rod (70), axially sliding on, or in, a cross-beam body (60).
 28. Clamp means according to claim 27, wherein said actuating rod (70) is connected to a rocker arm (72).
 29. Clamp means according to claim 28, wherein said rocker arm is arranged for driving a couple of actuating levers (74).
 30. Clamp means according to claim 29, wherein said couple of actuating levers (74) is arranged for controlling friction pads (76) through swinging levers (78) interacting with respective elastic means (80).
 31. Clamp means according to claim 27, wherein said actuating rod (70) acts on the ends of a couple of driven rods (84) carrying the friction pads (76) at the opposite ends.
 32. Clamp means according to claim 31, wherein said couple of driven rods (84) interacts with elastic return means (88).
 33. Clamp means according to claim 31, wherein said actuating rod (70) acts on said couple of driven rods (84) through inclined planes (86).
 34. Method for working semi-worked elements, comprising placing a semi-worked piece (P) in a working station (14), characterized in that, substantially simultaneously to said placing it is further provided placing a semi-worked piece (P) to be worked in a loading station (6) and extracting a semi-worked piece (P) already worked from an unloading station (8).
 35. Method according to claim 34, wherein said placing comprises rotating supporting means (16, 5), to which said semi-worked piece is fixed, about a service axis (Z).
 36. Method according to claim 34, wherein said placing comprises rotating supporting means (16) about a working axis (Z1; Z2; Z3).
 37. Method according to any one of claims from 34 to 36, wherein said rotating comprises rotating first supporting means (16).
 38. Method according to any one of claims from 34 to 37, wherein said rotating comprises rotating second supporting means (5).
 39. Method according to any one of claims from 34 to 38, wherein said rotating comprises alternatively rotating said first supporting means (16), or said second supporting means (5). 